Marinococcus luteus sp. nov., a halotolerant bacterium isolated from a salt lake, and emended description of the genus Marinococcus.

A Gram-positive, aerobic, motile, coccoid, orange-pigmented bacterium, designated strain YIM 91094(T), was isolated from a salt lake sample collected from Barkol Lake in Xinjiang Province, north-west China. The strain was able to grow at pH 6.0-8.0 (optimal growth at pH 7.0), at 10-37 degrees C (optimal growth at 28 degrees C) and in the presence of 0-25 % (w/v) NaCl [optimal growth in the presence of 10-15 % (w/v) NaCl]. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain YIM 91094(T) was affiliated with the genus Marinococcus and exhibited levels of sequence similarity of 99.2 % to Marinococcus halotolerans YIM 70157(T) and 99.7 % to Marinococcus halophilus DSM 20408(T). However, it showed moderately low levels of DNA-DNA relatedness with the above type strains (56.0 and 57.5 %, respectively). The peptidoglycan type of strain YIM 91094(T) was A1gamma, with meso-diaminopimelic acid as the diagnostic diamino acid. MK-7 was the predominant menaquinone and anteiso-C(15 : 0) (49.9 % of the total) and anteiso-C(17 : 0) (29.6 %) were the major cellular fatty acids. The DNA G+C content was 48.7 mol%. Strain YIM 91094(T) possessed chemotaxonomic markers that were consistent with its classification in the genus Marinococcus. On the basis of the data presented, strain YIM 91094(T) is considered to represent a novel species of the genus Marinococcus, for which the name Marinococcus luteus sp. nov. is proposed. The type strain is YIM 91094(T) (=KCTC 13214(T)=CCTCC AA 208014(T)). An emended description of the genus Marinococcus is provided.